title: Obesity and mortality after breast cancer by race/ethnicity: The California Breast Cancer Survivorship Consortium.
abstract: We investigated body size and survival by race/ethnicity in 11,351 breast cancer patients diagnosed from 1993 to 2007 with follow-up through 2009 by using data from questionnaires and the California Cancer Registry. We calculated hazard ratios and 95% confidence intervals from multivariable Cox proportional hazard model-estimated associations of body size (body mass index (BMI) (weight (kg)/height (m)(2)) and waist-hip ratio (WHR)) with breast cancer-specific and all-cause mortality. Among 2,744 ascertained deaths, 1,445 were related to breast cancer. Being underweight (BMI <18.5) was associated with increased risk of breast cancer mortality compared with being normal weight in non-Latina whites (hazard ratio (HR) = 1.91, 95% confidence interval (CI): 1.14, 3.20), whereas morbid obesity (BMI ≥ 40) was suggestive of increased risk (HR = 1.43, 95% CI: 0.84, 2.43). In Latinas, only the morbidly obese were at high risk of death (HR = 2.26, 95% CI: 1.23, 4.15). No BMI-mortality associations were apparent in African Americans and Asian Americans. High WHR (quartile 4 vs. quartile 1) was associated with breast cancer mortality in Asian Americans (HR = 2.21, 95% CI: 1.21, 4.03; P for trend = 0.01), whereas no associations were found in African Americans, Latinas, or non-Latina whites. For all-cause mortality, even stronger BMI and WHR associations were observed. The impact of obesity and body fat distribution on breast cancer patients' risk of death may vary across racial/ethnic groups.
authors.forename: Marilyn L
authors.initials: ML
authors.lastname: Kwan
authors.forename: Esther M
authors.initials: EM
authors.lastname: John
authors.forename: Bette J
authors.initials: BJ
authors.lastname: Caan
authors.forename: Valerie S
authors.initials: VS
authors.lastname: Lee
authors.forename: Leslie
authors.initials: L
authors.lastname: Bernstein
authors.forename: Iona
authors.initials: I
authors.lastname: Cheng
authors.forename: Scarlett Lin
authors.initials: SL
authors.lastname: Gomez
authors.forename: Brian E
authors.initials: BE
authors.lastname: Henderson
authors.forename: Theresa H M
authors.initials: TH
authors.lastname: Keegan
authors.forename: Allison W
authors.initials: AW
authors.lastname: Kurian
authors.forename: Yani
authors.initials: Y
authors.lastname: Lu
authors.forename: Kristine R
authors.initials: KR
authors.lastname: Monroe
authors.forename: Janise M
authors.initials: JM
authors.lastname: Roh
authors.forename: Salma
authors.initials: S
authors.lastname: Shariff-Marco
authors.forename: Richard
authors.initials: R
authors.lastname: Sposto
authors.forename: Cheryl
authors.initials: C
authors.lastname: Vigen
authors.forename: Anna H
authors.initials: AH
authors.lastname: Wu
mesh_terms: D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D001213:Asian / Q000706:statistics & numerical data; D001837:Body Weights and Measures; D001943:Breast Neoplasms / Q000208:ethnology* / Q000401:mortality*; D002140:California / Q000453:epidemiology; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000208:ethnology*; D009767:Obesity, Morbid / Q000208:ethnology; D044469:Racial Groups / Q000706:statistics & numerical data*; D012111:Residence Characteristics; D012959:Socioeconomic Factors; D016019:Survival Analysis; D013851:Thinness / Q000208:ethnology
keywords: adiposity; body mass index; breast cancer; mortality; obesity; race/ethnicity; survival; waist-hip ratio